The stone mushrooms are rock formations, which are located to the east of the village of Beli Plast, on the road connecting Kardzhali with Haskovo.
The rock formations have the form of natural mushrooms – their stones are pink and the hats greenish. The height of the stumps and the width of the hats is up to 2.5 m. They are sculpted in rhyolite volcanic tufts. The tufted mushrooms are the result of intensive underwater volcanic activity dating from the time of the Palaeogene. Following the withdrawal of the sea and the successive rise of the seabed, erosion began to work on them. The lower, pink layer was softer and more easily yielding to the action of the sun, the wind and the rain. The upper, greenish layer contains stronger minerals, especially volcanic glass, and it is harder to get out. So for thousands of years has formed a wonderful composition of unique shapes and colours.
According to a legend, Coal Raduil lived in the fortress of Perperikon together with his four beautiful daughters. One sunny morning went for water outside the fortress walls. Suddenly, on the hill behind the river, they saw a great horde of invaders. Begom returned to the fortress. It started a hot but unequal battle. Many of the men were killed, and many women were captured. Among them were Raduil’s daughters.
They led them to the Horde’s leader, straddling a racing horse near the nearby river – to look around and set the most beautiful ones for themselves, and the rest to sell for slaves. As soon as they approached him, rage caught the hearts of the girls. They picked up what they found – trees, stones, and started throwing up the horseman. The horse frightened, standing on his hind legs, and the unsuspecting rider fell to the ground. The four maidens rushed to him and tore him. Then they fled to the nearby forest.
The driver’s closest friend ran to chase the girls. At the sunset, they caught up with them, swung the yatagan and cut off the head of the first. As soon as she touched the ground, she turned into a stone sponge. The same was repeated with the other two sisters. Before she dug the last girl’s head, she turned into a stone. Terrible, he began to escape with his horse, but in the first step, he became a black rock. Today, people call the lonely rock near the Karatepe mushrooms.